Abstract: System for mechanically assisting rehabilitation of a patient. The system includes: a manipulator having at least five degrees of freedom and defining a free end; a limb support for supporting a limb of the patient, and secured relative to the free end of the manipulator; a force sensor operatively connected to the limb support to allow measuring input forces applied by the patient; and a processor communicatively connected to the force sensor, the manipulator, and a memory store which defines a scale factor. The processor is configured to control operation of the manipulator to move the limb support, and further configured so that responsive to receiving an input force measurement from the force sensor, the processor determines an applied force as a function of the input force and the scale factor.